Does QtAVPlayer work with FFMPEG 7 ?

[geminixdev]

When looking through qtmultimedia changes update below hints for possible differences with Ffmpeg 7 in hw accelerated decoding and rendering:

https://codereview.qt-project.org/c/qt/qtmultimedia/+/560858

Old FFmpeg versions expose supported hw formats in codec->pix_fmts, whereas FFmpeg 7.0, and partially FFmpeg 6.1, expose the formats in hw_config.

The patch uses both of them to support the best compatibility.

Pick-to: 6.7 6.5